In contemporary road vehicles, personal safety has become an increasingly important issue to drivers and passengers of such vehicles. Of particular concern regarding safety is damage resulting from frontal and lateral vehicle impacts. One conventional approach to render vehicles more resistant to impacts and crashes is by enhancing the structural strength of such vehicles. Such structural strength enhancement can be achieved by including strengthened frames in vehicles, for example by including horizontal strengthening sills, roof sills, transverse strengthening members and so forth. However, analysis of vehicle accidents has shown that structural strength enhancement alone does not provide an optimal solution as kinetic energy in crash situations has to be dissipated somewhere and, when not absorbed, can have unpredictable effects as momentum is transferred between vehicles involved in crashes, for example vehicles involved can roll or jack-knife potentially into paths of other vehicles. It is therefore conventional practice to try to absorb at least some kinetic energy in crash situations, for example by including crumple zones within vehicles. Whereas crumple zones can be conveniently included in front regions of vehicles, for example in front engine compartments where there is often free space, it is generally not so straightforward to design crumple zones for coping with lateral vehicle impacts and crashes. Such lateral vehicle impacts and crashes are not uncommon, especially at road junctions and at traffic lights when vehicle drivers have not been sufficiently attentive.
Various approaches have been conventionally adopted for providing lateral crash energy absorption in vehicles. For example, in a published European patent application no. EP 1 134 148, there is described a frame structure for a vehicle. The frame structure is alleged to be capable of increasing collision energy absorption and includes a floor member with extruded side sill members which are adapted to undergo a lateral buckling response to side collisions whilst resisting axial or longitudinal deformation due to end-on collisions. The sill members are orientated with their elongate axes substantially running from a front region of the vehicle to a rear region thereof.
As a further example of conventional approaches to coping with lateral impact in vehicles, a published United Kingdom patent application no. GB 2 392 652 describes side-panel occupant protection. In such protection, a vehicle side door comprises an inner trim panel, an outer panel and a pusher block arrangement. The pusher block arrangement is aligned with a pelvic region of an occupant of the vehicle. The pusher block is operable to be displaced towards the occupant if the outer panel is deformed due to a side impact. An air bag is provided for inflation into a region between the trim panel and the pelvic region of the occupant so as to transfer the load, in an impact, from the pusher block arrangement to the occupant for moving the occupant away from the door. Optionally, the pusher block arrangement comprises two separate components, namely an inner block and an outer block. The blocks are optionally fabricated from an energy-absorbing material such as a foam.
Although such conventional approaches for absorbing kinetic energy in impact or crash situations are alleged to be of benefit, they are potentially not capable of providing an adequate degree of kinetic energy absorption in many contemporary vehicles, for example in open-top vehicles. Such lack of protection against lateral impact represents a technical problem, for example when vehicles with relatively elevated chassis height such as SUVs (sport utility vehicles), vans and trucks impact into road vehicles with relatively lower chassis heights.
Thus, the present invention is concerned with providing improved impact energy absorption, for example by way of advanced energy absorption structures.